CHAPTER 1. The Potential Contribution of Photoelectrochemistry in the Global Energy Future

Abstract

This chapter examines the potential for photoelectrochemical (PEC) energy conversion to contribute to the future global energy supply. The hope is that it will be a guide to researchers in selecting problems that, if solved, will have a realistic chance to help mitigate the problems of climate change and provide clean sustainable sources of energy. The chapter starts with a brief history of PEC energy conversion and the early development of PEC photovoltaic cells. We then argue that the real contribution of photoelectrochemistry is to perform solar water splitting to renewably produce hydrogen and provide a path into the hydrogen economy, the preferred sustainable fuel-based economy. We then present arguments against PEC carbon dioxide reduction as a path to liquid fuels based on both scale, economic and qualitative thermodynamic considerations. PEC hydrogen could aid liquid fuels production by reacting it with gasified coal or biomass and save energy and carbon dioxide emissions by replacing methane as a source of hydrogen in the production of ammonia.